Background: Published reports demonstrate that the use of Castor stent-graft is a promising treatment of aortic pathologies with the need to land in zone 2. However, there is a lack of publications on the medium-term results of Castor in the European population. This research evaluates the mid-term results of the Castor stent-graft in several Polish centers for the treatment of aortic pathologies and enriches the current knowledge of Castor stent-grafts. Material and methods: Twenty-one patients from 5 polish vascular surgery centers in subacute phase of type B aortic dissection (TBAD) with at least 1 classic risk factor of aneurysmatic degeneration, thoracic aortic aneurysms (TAAs) exceeding 5.5 cm, subacute phase of intramural hematomas (IMHs) and penetrating aortic ulcerations (PAUs) with at least 1 indication to endovascular treatment. Structure of the aortic arch and factors of aneurysmal degeneration for TBAD were highlighted. Early complications, long-term complications, and reinterventions after Castor device implantation are reported in the study. Results: Twenty (95.24%) patients survived, of which a technical success involving implantation of the Castor device in the correct location with a patent branch for the left subclavian artery, and no endoleaks were noted in 19 (90.48%) patients. After the procedure, there were 2 (9.52%) cases of type I endoleak (in which technical success was not achieved) and 2 (9.52%) cases of bird beak. In addition, 1 case of access site hematoma, 1 case of pseudoaneurysm, and 1 case of access iliac artery rupture requiring implantation of a Viabahn device were observed. During the follow-up period (mean 14 months; range = 1-40 months), 1 patient required reintervention due to type I endoleak and 1 patient due to left subclavian artery (LSA) branch thrombosis. Two patients required subsequent branched endovascular aortic repair procedure due to unfavorable remodeling and fast aneurysm formation in visceral aorta, regardless of Castor results. Conclusion: The Castor device is an easy-to-use stent-graft with good medium-term results. It is an excellent option in cases requiring LSA revascularization during TEVAR. Clinical Impact In this study, we investigate the medium-term results of the Castor stent graft in patients with type B aortic dissection, thoracic aortic aneurysm, intramural hematoma and penetrating aortic ulceration. The medium-term results of treatment with the Castor device are not yet well studied. Currently, there are only a small number of publications on the safety, complications and success of Castor device implantation.